The invention relates to a valve, having parts that are heat-sensitive above a limit temperature, a housing and at least one connecting tube to which a pipe is arranged to be soldered using local heating, and to a method for producing such a soldered joint.
In refrigeration systems, materials processing systems and similar systems, it is usual to join the expansion valves, magnetic valves, check valves and so on to their associated pipework by soldering. Copper pipes are used extensively for this pipework. The connecting tubes of the valves also consist of copper or a similar material. So that the heat-sensitive parts of the valve, for example, plastics parts, O-rings or a vapour, liquid or solid filling used in the valve are not damaged as the pipes are soldered together, previously, cooling had to be effected during the soldering operation. It is therefore usual to position so-called "cooling tongs" next to the soldering,point, or to wrap the valve housing in a damp cloth so that the valve housing does not become too hot.
The invention is based on the problem of simplifying the soldering operation.
This problem is solved according to the invention in that the connecting tube consists of a material of such low thermal conductivity that the heat-sensitive parts remain below the limit temperature as the heat required for soldering is applied.